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If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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01 Nov 2019, 03:11
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Competition Mode Question If A and B are positive integers and 5A 7(B + 3) = 2, what is the least possible value of AB? (A) 1 (B) 3 (C) 5 (D) 7 (E) 9 Are You Up For the Challenge: 700 Level Questions: 700 Level Questions
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Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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01 Nov 2019, 04:07
5A 7(B + 3) = 2 5A7B21=2 5A7B=23
As A and B are positive intergers and from answer choices we know that A>B. lets do trial and error: Lets say A=5, then B=ve. not possible Say A=6, then B=1 Therefore, AB=5 Ans: C



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If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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Updated on: 03 Nov 2019, 23:59
5a7b=23 a=6 and b = 1 61 ;5 IMO C
If A and B are positive integers and 5A 7(B + 3) = 2, what is the least possible value of AB?
(A) 1 (B) 3 (C) 5 (D) 7 (E) 9
Originally posted by Archit3110 on 01 Nov 2019, 04:54.
Last edited by Archit3110 on 03 Nov 2019, 23:59, edited 1 time in total.



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Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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01 Nov 2019, 05:00
5A7B=23 A and B are positive integers 5(6)7(1)=23 (A=6, B=1) AB= 5 option C is the correct option
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If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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Updated on: 25 Feb 2020, 21:22
If A and B are positive integers and 5A 7(B + 3) = 2, what is the least possible value of AB? (A) 1 (B) 3 (C) 5 (D) 7 (E) 9 Since A  B has to be positive as per the answer choices, A > B. So, let's take B = 1 (only then A > B as both are positive) 5A 7(B + 3) = 2 5A 7B  21 = 2 5A  7B = 23 5A  7 * 1 = 23 A = 6 B = 1 and A = 6 are the least possible positive integer values Hence A + B = 7 A  B = 5 IMO Answer C.
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Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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01 Nov 2019, 07:24
5A 7(B + 3) = 2,
Least value of B=1....then A=6
The least possible value of AB=5
OA:B
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Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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01 Nov 2019, 09:22
If A and B are positive integers and 5A 7(B + 3) = 2, what is the least possible value of AB?
5(AB) = 23+2B Least possible value of B is 1 => Least possible value of 5(AB) is 23+2=25 IMO C



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If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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Updated on: 26 Dec 2019, 04:05
Substitutefrom given eauation, the value of A into AB We get AB = (23+2B)/5 . For this expression to be minimum B must be minimum which is 1. Hence expression = [23 + 2(1) ]/5 = 5 = C
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Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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01 Nov 2019, 12:47
As per the question,
5A  7B 21 = 2 => 5A  7B = 23 => 5(AB) = 23 + 2B => AB = (23+2B)/5 Since A and B are positive integers and we have to find the minimum value of AB, we have to consider the minimum possible value of B as per the previous expression.
Min. B = 1 Therefore, min. (AB) = 5 Answer is (C)
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Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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01 Nov 2019, 13:46
A, B — positive integer 5A —7(B+3)= 2 —> what is the least possible value of A —B =???
5A —7B —21=2
5A —5B —2B =23
5*( A—B)= 23+ 2B
A —B= (23+ 2B)/5 —> in order A—B to be the least value, B should be equal to 1.
B=1 —> A —B = (23+2)/5= 5
The answer is C
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Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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01 Nov 2019, 14:53
C is my answer.
5A 7(B + 3) = 2 or, 5A=23+7B. Min value of B=1, So min value A=6 So min value (AB)=5



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Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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01 Nov 2019, 14:55
C is my answer.
5A 7(B + 3) = 2 or, 5A=23+7B. or, A=23/5 + 7/5 B So the difference between A & B is greater than 23/5 or 4.5. So the minimum difference is 5 (since IntegerInteger=Integer and Minimum integer greater than 4.5 is 5)



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Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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01 Nov 2019, 15:16
answer should be a , 5(ab)+2b=23 for ab to be minimum 2b must be equal to 18



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Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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01 Nov 2019, 21:51
5A  7B  23 = 2 5A  7B = 25 Because the result (25) is multiple of 5, 7B also should be multiple of 5. (Ex: 7*5= 35 (least number)) 5A  7*5 = 25 5A = 60 A = 12 and B =5 AB= 125 = 7 Ans is: D



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Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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02 Nov 2019, 00:11
5A 7(B + 3) = 2 > 5A  7B = 23 > 5A  5B = 2B + 23 > A  B = (2B + 23)/5
Least possible value of A  B is when B = 1 > A  B = (2*1 + 23)/5 = 25/5 = 5
IMO Option C



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Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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02 Nov 2019, 12:07
Given : 5A 7(B + 3) = 2 and A,B are positive integers
5A  7B  21 = 2 5A  7B = 23 5A  5B 2B = 23 5(AB) = 23 + 2 since the least positive value of B is 1 5(AB) = 25 AB = 5
Answer is C



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Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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03 Nov 2019, 14:50
Quote: If A and B are positive integers and 5A 7(B + 3) = 2, what is the least possible value of AB?
(A) 1 (B) 3 (C) 5 (D) 7 (E) 9 5A 7(B + 3) = 2 5A 7B = 2 + 21 5A = 23 + 7B A = (23 + 7B) / 5 (A,B) = positive integers A = (23 + 7B) / 5 = positive integer B = 1; A = 23+7/5 = 30/5 = 6 B = 2; A ≠ integer B = 6; A = 23+7(6)/5 = 65/3 = 13… min. AB = 61 = 5 Answer (C)



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Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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13 Dec 2019, 06:36
Bunuel wrote: Competition Mode Question If A and B are positive integers and 5A 7(B + 3) = 2, what is the least possible value of AB? (A) 1 (B) 3 (C) 5 (D) 7 (E) 9 Are You Up For the Challenge: 700 Level Questions: 700 Level Questions5A 7(B + 3) = 2 5A7B = 23 B = (5A23)/7 When A=6; B=1; AB = 5 When A=13;B=6; AB =7 AB increases further e.g. A=20;B=11; AB = 9 IMO C



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Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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25 Feb 2020, 20:41
5A 7(B + 3) = 2 can be written as 5(AB)23 = 2B Hence option A and B is easy to eliminate as A and B are positive integers. In option C, AB = 5, which gives B=1 (Satisfies the constraint ) Hence correct answer No need to look for option D and E as the question asked the least possible value of AB Hence C




Re: If A and B are positive integers and 5A 7(B + 3) = 2, what is the lea
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25 Feb 2020, 20:41






